Set light color from python script
Test code out in the console.

Even if you are going to use a script from command line always (IMO) a good idea to test it out in the python console. (D = bpy.data, C = bpy.context)

When adding an object via operator, the new object added is the  context.object  Notice the name below is not "Area" as there are already other area lights in the scene.  Using light_ob = bpy.data.objects["Area"] will only work as expected if there are no other lights of that name in the blend file.

&gt;&gt;&gt; bpy.ops.object.light_add(type='AREA')
{'FINISHED'}

&gt;&gt;&gt; C.object #  the new object
bpy.data.objects['Area.002']


At any time can hit the autocomplete to see the available options.  The light is the data part of the light object.  (In the UI Properties panel it is under the Data tab.)

&gt;&gt;&gt; light_ob = C.object
&gt;&gt;&gt; light = light_ob.data
&gt;&gt;&gt; light
bpy.data.lights['Area.002']


It's of type AreaLight which per documentation link posted in question is a subclass which inherits properties of bpy.types.Light

&gt;&gt; type(light)
&lt;class 'bpy.types.AreaLight'&gt;

&gt;&gt;&gt; light.energy = 500


All objects have an rgba color property. For a lamp as commented above to set the lamp color set it on the data part. 

&gt;&gt;&gt; light.color = (1, 0, 0)
&gt;&gt;&gt; 


The script. 

import bpy


bpy.ops.object.light_add(type='AREA')
light_ob = bpy.context.object
light = light_ob.data
light.energy = 500
light.color = (1, 0, 0)